LA GLORIA , Mexico -LRB- CNN -RRB- -- Tucked away in this small mountain village , off a dusty road flanked by pig farms , is where the earliest case of swine flu -- a virus spreading globally -- was confirmed .

Five-year-old Edgar Hernandez , known as `` patient zero '' survived the earliest documented case of swine flu .

Meet the child known as `` patient zero '' by his doctors -- 5-year-old Edgar Hernandez , who survived the earliest documented case of swine flu in an outbreak that , officials say , has now spread across four continents .

His family lives in the 3,000-population village of La Gloria in the state of Veracruz , where a flu outbreak was reported on April 2 . State officials arrived and took samples from dozens of people .

Lab tests confirmed that Edgar was the only patient in Veracruz to test positive for the swine flu virus ; the others had contracted a common flu . Health officials had returned to Edgar 's sample only after cases of the new flu strain were spotted around the country .

`` In this case , there 's a patient who turned out to be positive for the swine-flu virus , with the exception that at that time in no region of the world it had been established as an etiological , epidemic cause , '' said Mexico Health Secretary Jose Angel Cordova .

Edgar has managed to bounce back from his symptoms and playfully credits ice cream for helping him feel better .

His mother blamed the virus on a huge pig farm in the neighborhood . Officials have conducted tests at the farm owned by U.S. company Smithfield Foods , and those tests came back negative .

Meanwhile , Mexican health officials suspect the swine flu outbreak has caused more than 159 deaths and roughly 2,500 illnesses .

The World Health Organization says at least 105 cases have been confirmed worldwide , including 64 in the United States ; 26 in Mexico ; six in Canada ; three in New Zealand ; and two each in Spain , the United Kingdom and Israel . WHO has confirmed deaths only in Mexico , where seven people have died from swine flu .

The deadly outbreak in Mexico prompted authorities to order about 35,000 public venues in Mexico City to close or serve only take-out meals as health officials tried to contain the virus . iReport.com : Are you worried about swine flu ?

Officials in Mexico City also ordered the closing of bars , clubs , movie theaters , pool halls , theaters , gyms , sport centers and convention halls until May 6 , said Juan Jose Garcia Ochoa , one of the city government 's top officials .

Officials on Friday closed schools in the city and Monday extended that order nationwide until at least May 6 .

`` I 'm pretty nervous of this whole virus thing , '' Berta Hernandez said as she touched up her eyeliner inside a packed and humid subway car in Mexico City . She did not dare lift her surgical mask to put on lip gloss .

`` I 'm nervous of the people who are n't wearing masks . Maybe they will suddenly sneeze or cough , '' she said .

Governments around the world scrambled to prevent further outbreak .

Some , like China and Russia , banned pork imports from the United States and Mexico , even though the World Health Organization said the disease `` has not been shown to be transmissible to people through eating properly handled and prepared pork -LRB- pig meat -RRB- or other products derived from pigs . '' Several others , such as Japan and Indonesia , used thermographic devices to test the temperature of passengers arriving from Mexico .

The Philippines ' health department urged people to avoid kissing and hugging in public . Argentina announced a five-day ban on flights from Mexico . Four cruise lines -- Holland America , Royal Caribbean , Norwegian and Princess -- canceled upcoming calls to Mexican ports .

President Obama said the outbreak is a cause for concern , not for alarm . The government urged travelers to avoid nonessential travel to Mexico . iReport.com : `` Regular life '' in Mexico with masks

The U.S. Food and Drug Administration issued emergency authorization for the use of two of the most common antiviral drugs , Tamiflu and Relenza . The authorization allows the distribution of the drugs by a broader range of health-care workers and loosens age limits for their use .

In Mexico City , however , there is a shortage of such medication . It also became impossible to find protective surgical masks , which the government had handed out to one out of every five residents . Watch Dr. Sanjay Gupta inside a Mexico City hospital ''

Worried citizens continue to flood in night and day at hospitals , only to be turned around by armed guards .

`` I was looking for a mask at my local pharmacy , but they sold out , '' supermarket worker Rafael Martinez said as he rode the subway . `` I know it 's a risk , but I ca n't find one . ''

Swine influenza , or flu , is a contagious respiratory disease that affects pigs .

When the flu spreads person-to-person , instead of from animals to humans , it can continue to mutate , making it harder to treat or fight , because people have no natural immunity .

Symptoms include fever , runny nose , sore throat , nausea , vomiting and diarrhea .

Common seasonal flu kills 250,000 to 500,000 people every year worldwide , far more than the current outbreak of swine flu . Learn more about swine flu and how to treat it ''

But there is no vaccine for the new disease , and little natural immunity , an expert said .

`` I think the reason to be concerned is ... we had a vaccine for regular flu , '' said Dr. Carlos del Rio of the Emory University School of Medicine in Atlanta , Georgia . `` This is a totally new virus . ... You have a virus to which there 's no pre-vaccination , there 's no prior immunity . And , therefore , the mortality rate may be higher than other influenza viruses . '' Watch why swine flu is a `` sloppy virus '' ''

Researchers do not know how the virus is jumping relatively easily from person to person , or why it 's affecting what should be society 's healthiest demographic .

Meanwhile , Mexico 's largest city saw the the government close universities , postpone sporting events and cancel church services in an effort to try to stem the spread of the virus .

`` I do n't think it 's feasible or advisable to shut down the city , '' said Jose Luis Suarez , a newspaper vendor . `` People would try and get out somehow , and that would make a bad situation worse . ''

CNN Chief Medical Correspondent Dr. Sanjay Gupta in La Gloria , Mexico , contributed to this report .

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NEW : Boy , 5 , with first documented case and only in village , recovering

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64 cases confirmed in United States , CDC says

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Thousands flood Mexican hospitals , scramble for masks

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WHO notes significant human-to-human transmission , a step toward pandemic